The present invention relates to reducing the amount of power used by computing devices and, more particularly, to reducing the amount of power wasted by an imaging device by determining the time of entry and/or exit by the imaging device into/from a reduced power mode based on device usage statistics.
Computing devices, such as imaging devices, consume substantial power. To make these devices more power efficient, manufacturers have equipped these devices with reduced power modes, sometimes called “sleep” modes. While in a reduced power mode, the supply of power to selected components of these devices (e.g. front panel, electromechanical elements, processing elements) is cutoff or reduced.
Many imaging devices automatically enter and/or exit reduced power modes at defined times. For example, some imaging devices automatically place themselves into a reduced power mode after a period of nonuse defined by a power save entry timeout value and, if not earlier awakened by a job request, automatically awaken from the reduced power mode after a period in the reduced power mode defined by a power save exit timeout value. Power save entry and/or exit timeout values are often configured by a human administrator and can vary anywhere from a few minutes to several hours. On some of these devices, these timeout values can also be made to vary with time of day (for example, 20 minute entry timeout value from 6 a.m. to 6 p.m., five minute entry timeout value from 6 p.m. to 6 a.m.). Regardless, in the interval between last use of the device and entry into the reduced power mode, and the interval between wakeup from the reduced power mode and first use of the device, these devices still waste considerable power. The amount of wasted power can be particularly significant at night when an imaging device remains awake after completing a management job, even though there is little chance the device will receive another job before the power save entry timeout value is reached. On the other hand, premature entry into a reduced power mode can also be extremely costly due to high energy usage during power-up cycles.
A significant contributor to wasted power in imaging devices that automatically enter and exit reduced power modes at defined times is imprudent selection of power save entry and exit timeout values. A human administrator may select entry and exit timeout values for an imaging device based largely or entirely on conjecture rather than objective analysis. Moreover, a human administrator is often responsible for configuring entry and exit timeout values on dozens or hundreds of imaging devices at multiple sites. For reasons of administrative convenience, such an administrator may configure all of these devices with the same entry and exit timeout values, even though usage patterns on these devices vary widely.